In recent years, the circuit of a color television receiving set has been divided into a plurality of sections according to the functions thereof and to form respective sections as independent integrated circuit units. More particularly, nearly all of the circuit sections starting from an image intermediate frequency amplifier circuit to a color demodulation circuit are formed as integrated circuit units and only such circuits as portions of the output stage which require a high power are constructed by transistor circuits. In such a transistorized circuit, however, since the existing circuit is sectionalized and each section is transistorized, the number of the integrated circuit units increases as the number of the circuit units increase. Accordingly, efforts have been made to form integrated circuit units capable of providing the functions of a plurality of circuit sections for the purpose of decreasing the number of the integrated circuit units. For example, it has been tried to combine three integrated circuit units for the band amplifier, color demodulation circuit and color synchronizing circuit respectively of a color television receiving set into a single integrated circuit using having multiple functions, thereby increasing the efficiency of integration. In such multifunction integrated circuit unit, however, it is necessary to provide pins for connecting it with external circuits of the number equal to the number of the pins of three independent integrated circuit units thus increasing the size of the multifunction integrated circuit unit. Of course it is desirable to decrease as far as possible the number of such pins. It is also necessary to incorporate into such multi-function integrated circuit unit a voltage controlled type oscillation circuit, a phase control circuit and a phase shifting circuit for use in a demodulation circuit. However, at present, as it is difficult to incorporate the phase shifting circuit into the integrated circuit unit, it is obliged to construct the phase shifting circuit as an element outside of the integrated circuit unit. Accordingly, it is necessary to provide a large number of pins for the integrated circuit unit for connecting it with external or peripheral circuit elements thus increasing the size of the integrated circuit unit.
Although a multi-function integrated circuit unit is advantageous in that it can decrease the number of independent integrated circuits it is also desirable to provide multifunction unit circuits for the integrated circuit unit for the purpose of providing a more efficient multi-function integrated circuit unit.